Propose a batch: L1 (first contact)L1 ✈ special postage (post-office run)L2 (+70d after L1)L3 (+112d after L2)L4 (+243d after L3)Nurture (annual, +365d) size Propose → machine gathers the ones due, drops replied/DNC/held, one per owner-group

Sequence intervals (days): L1→L2 L2→L3 L3→L4 L4→Nurture Save intervals measured from the previous letter's post date · shared across the team